Effect of cycocel and biofertilizers on yield and some ‎growing indices of wheat under irrigation withholding condition

In order to study of yield and some growing indices of wheat (Triticum aestivum L.) in response to the biofertilizers and cycocel under water limitation conditions, a factorial experiment based on a randomized complete block design with three replications was conducted at the research farm of faculty of agricultural sciences, University of Mohaghegh Ardabili, during 2015-2016 cropping season. Factors were water limitation at three levels (full irrigation as control, irrigation withholding in 50% of heading and booting stages as moderate and severe water limitation respectively, according to 45 and 59 Zadoks code), seed inoculation with biofertilizers at four levels (without inoculation as control, seed inoculation with Azotobacter chrocoocum strain 5, Pseudomonas putida strain 186 and inoculation with Azotobacter+ Pseudomonas) and foliar application of cycocle at four levels (0, 400, 800 and 1200 mg L-1). Means comparison showed that maximum grain yield (3822 kg ha-1), total dry matter (2720 g m-2), crop growth rate, net assimilation rate, seed protein and chlorophyll content, increased due to seed inoculation with Azotobacter+ Pseudomonas and foliar application of 1200 mg L-1 cycocle under normal irrigation. The combined use of Azotobacter and Pseudomonas bacteria and foliar application of 1200 mg.L-1 showed a significant increase in root dry weight. Foliar application of 1200 mg.L-1 cycocle and seed inoculation with Azotobacter and Pseudomonas increased grain yield 63.41, 52.90 and 62.46%, respectively, at full irrigation, irrigation to 50% of heading and booting stages in comparison with no application of bio fertilizers and cycocel. Generally, it seems that the application of biofertilizers and cycocel can be a proper tool for increasing wheat yield under water limitation.